A relatively modern medical technology known as blood component therapy involves administering to a patient just that part of the blood that he actually needs. Rather than whole blood, the physician decides what portion or component of blood is necessary for the patient and administers only that component to him. He, thus, avoids many of the hazards which are inherent in whole blood usage. Not only is the practice better for the patient in that certain risks involving transfusing whole blood are reduced, but it permits one unit of donated blood to be used for more than one patient. For example, from one unit of whole blood, which subsequently is fractionated, there may be derived red blood cells, platelets, fresh plasma, frozen or stored plasma, albumin, globulins and the like.
Furthermore, in the most modern techniques, cell separators permit the separation of blood into its components while the donor is in the process of making a donation. Through modern technology it is possible for a blood bank to take from the donor specific components which are needed by a patient while other components are returned simultaneously to the donor.
In the technique known as plasmapheresis, the plasma is separated from the cellular elements of the blood and the cells returned to the donor. The plasma is then subsequently used for blood volume expansion or blood augmentation in the form of stored plasma or fresh frozen plasma. The plasma can also be processed into any number of useful products such as albumin, globulins and antihemophiliac factor. It is to this purpose that the present invention is directed.
Blood is collected from the donor in a connected, sealed collection system and then centrifuged to separate the cells and the plasma. The cells are returned to the donor and the plasma is subsequently frozen in the collection bag. In the frozen state the plasma may be stored for a number of months before being removed for plasma component manufacturing. Subsequently, large quantities of plasma are batch processed, i.e., plasma from many donors.
During this batch processing contamination is an obvious risk. The whole blood is initially collected in a sealed system which is followed by centrifuging and freezing while still sealed. However, the bags must ultimately be cut open and the plasma removed either manually or automatically. It is possible that during the cutting and removing operation the plasma can become contaminated.